Howdy,
After I stopped fighting competitively, I taught BJJ for a while.
BJJ is a great sport and with a heavy gi on in summer, it knackers you!
Do be aware though, BJJ is somewhat full of politics and crap. I was personally kicked out of a gym in my fighting days because I tapped out the instructor's senior student. I was told it was 'not good for gym dynamics'. What a f'n joke!
John Will is a good person to base your training around if possible I believe.